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General Science / Re: So how big a nuclear bomb would it take to cover the UK with a tsunami anyway

« on: Yesterday at 20:23:59 »

As a guide to the size of a nuclear bomb needed to displace water, this is a 5mt bomb in an underground detonation. It is in soil, so the mass is about double that of water.

https://en.m.wikipedia.org/wiki/File:Project_Cannikin_Review.ogg#file

https://en.m.wikipedia.org/wiki/Cannikin

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General Science / Re: What would the kinetic energy of a bullet falling from 2Km be?

« on: Yesterday at 19:43:29 »

It does more than damage paul, the A rabs are wekk known for celebratory gunfire and thus deaths.

https://en.m.wikipedia.org/wiki/Celebratory_gunfire

 Not sure of the maximum velocity, ak47 bullets, like all warfare rifles are metal jacket points to conform to the Geneva convention so you would need to find it's resistance.

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Physiology & Medicine / Re: Can I utilise a telescope to enable me to see in the dark?

« on: Yesterday at 13:19:24 »

The relationship between depth of field and f-ratio is well established and is independent of the receptor. The eye can adapt very quickly to focus on a particular target  but the resolution of objects nearer and further than the target decreases in low light conditions as the pupil expands.

Yes, F stop on cameras are used to give the correct ammount of light. Engineered the correct way there would be no necessity for a small f stop.

I'm just wondering if it would work? Any biological reason why it would not?

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Question of the Week / Re: QotW - 24.12.12 - Is there any way to harness nuclear energy other than steam?

« on: 10/12/2024 23:08:03 »

The Americans and Soviets had "atoms for peace" programmes. It was harnessed largley in the method of excavations. But I assume the op is trying to convert nuclear energy into electrical?

Thermoelectric converters rarely reach 10% efficiencies

I'd this the same  device that powers space probes such as Pioneer which is why it is still going strong?

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Physiology & Medicine / Re: Can I utilise a telescope to enable me to see in the dark?

« on: 10/12/2024 17:26:09 »

But the depth of field problem, targeting all the light from the large apateur objective lens to the eyeball as if it where real world conditions should not result in a narrow depth of field. If the exit lens was projecting light in a similar manner to that which the eye percieves surely then the large light gathering capacity would just be a magnification of the eyes natural capability.

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Physiology & Medicine / Re: Can I utilise a telescope to enable me to see in the dark?

« on: 10/12/2024 00:03:59 »

Yes, but if you can take the light from an area greater area than the human eye would usually cover, at no greater magnification surely that would mean a higher level of light? Magnification in astronomical telescopes the light gathering capacity is offset by the magnification, you have to have icreace light to see things that are not visible with the human eye.

I am relying on some sort of lens wisardry for this theory.

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Physiology & Medicine / Re: Can I utilise a telescope to enable me to see in the dark?

« on: 09/12/2024 19:46:44 »

I understand Alan about powered light amplification devices, but I was thinking more passive. This is a rather large lens.
download.jpeg (4.89 kB . 275x183 - viewed 28 times)

That is a normal size 35 mm camera. So if I had a lens this size optimised for non magnifying  length with a field of view of 90 degrees would I be able to see in the dark? The area of the lens is many many times the area of the pupil, so even if a cats retina  is 100 times as sensitive as the human's this lens should theoretically be large enough.

I don't believe they see in any other wavelength than humans, unlike peregrine falcons or snakes.

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Physiology & Medicine / Can I utilise a telescope to enable me to see in the dark?

« on: 08/12/2024 17:54:20 »

Cats, dogs and other creatures are able to see in conditions I regard as pitch black by having more sensitive eyes which proves there must be light present and so I understand it light that is visible to humans. Now there are devices like binoculars that gather light over a greater area than the pupil, but the magnification means that the field of view is one of some distance away. Could I use similar methods to gather light without magnification to enhance my low light vision?

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Just Chat! / Re: Theories to start a new world.

« on: 08/12/2024 17:48:15 »

Last night I attempted to bring a taste of civilisation (live music) to a group seated in a place where they appear to worship a Roman instrument of torture - a huge illuminated crucifix. Strange things, people

"Onward Christian Soldiers marching as to war"?

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Physics, Astronomy & Cosmology / Re: Will AI really replace supercomputers for weather-forecasting?

« on: 07/12/2024 21:12:36 »

From what I understood weather forecasts go from 0.1 percent  reliable a long time in the furure to 99.9 percent just before the lightning bolt hits you, but never ever 100. It is done by running lots of different models and past information of similar weather. I an not sure how an AI is going to do this markedly differently, itself would probably be a supercomputer. If the a AI just takes a singular guess based on past learning it would surely be no different than now and perhaps, if possible less accurate.

https://www.cbsnews.com/news/microsoft-shuts-down-ai-chatbot-after-it-turned-into-racist-nazi/

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Physics, Astronomy & Cosmology / Re: Will AI really replace supercomputers for weather-forecasting?

« on: 06/12/2024 22:36:49 »

I do not see how AI can do without a super computer, AI at the minute is a targeted learning programme (narrow ai) that would only develop the same methods as existing programmes I should think, we cannot think of any other way of forecasting the weather so any narrow AI programme I should think will be along similar  requiring models of intricacy at vast scales. Maybe it could do it more efficiently, be more vigilant have more imagination and detail and become more accurate but I think it would still need the super computer models. If general ai could come up with another method rather than the 'model' method then we could get rid of the super computer. But we do not have general AI yet.

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Just Chat! / Re: Should Damage To The Prefrontal Lobe Be A Legal Defense?

« on: 05/12/2024 15:38:23 »

All depends if it affects you, some peoples brain can rewire some do not, it is usually decided on mental capability than physical evidence, the brain is still a great unknown.

https://www.newsweek.com/miracle-boy-born-no-brain-grows-back-1338637

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Just Chat! / Re: Theories to start a new world.

« on: 05/12/2024 12:26:27 »

I quite like this one Alan

I never did.

Oh, I thought you would have appreciated the brass jazzy aspects.

If we are to get rid of religion and stop people asking why, we must either get rid of scientists or stop people thinking such questions as what lies at the edge of the universe?

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Just Chat! / Re: Theories to start a new world.

« on: 04/12/2024 17:29:46 »

I quite like this one Alan

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Physics, Astronomy & Cosmology / Re: How does H20 wear away stone?

« on: 03/12/2024 22:46:25 »

Water is rarely present in pure form and in terms of geology there is almost always particulates and dissolved substances present.

Does this mean that water does in fact fail to damage hard rock, but is merely a conveyance device?

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Physics, Astronomy & Cosmology / Re: How does H20 wear away stone?

« on: 03/12/2024 18:19:40 »

Water can dissolve some components of stone (eg limestone), releasing the less soluble parts to be carried downstream.
- Moving water can carry sediment, which abrades the rock
- Water can get into cracks and freeze; expanding ice breaks off bit of rock.
- Salty water can get into rocks and evaporate; the salt crystals break the rock grains
- Frozen water (ie glaciers) can break off rocks, which then abrade other rocks.
- Ocean waves carry a lot of momentum, which breaks and erodes rocks

Thank you Evan. I am looking for how water itself rather than any other substances like salts wears away hard. Also as an interesting fact, a few years ago I learned than the freeze thaw action that everyone is taught actually is mostly to do with liquid water being subjected to pressure because of the ice expansion, basically high pressure fracturing.

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Physics, Astronomy & Cosmology / How does H20 wear away stone?

« on: 01/12/2024 22:20:06 »

It is often said water wears away stone, but does it really, in water jet cutting water is not actually much good at cutting hard materials unless an abrasive is added, garnet Ruby and saphire being common. So can an H20 drip really abrade stone.

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Just Chat! / Re: Theories to start a new world.

« on: 01/12/2024 22:07:17 »

something with a bit of comedy

Chemistry, Biology and Physics.

It must be useful there and then, nuclear physics just isn't going to be worthwhile. Depending on the constraints, material properties, material extraction and material production. If that's one as Materials Science then medicine and agriculture. Depends really whether you take this science as common knowledge.

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Just Chat! / Re: Should smartphones be banned from the dinner table?

« on: 01/12/2024 14:53:26 »

The photos and videos I do find not worthwhile, I do take photos, I have thousands built up over the years and I barely ever look at them, I have no real interest in looking at something I have already lived, other people will probably not be at all interested in 95%+ of them either, I do not have photos of dogs wearing hats or similar.


When camcorders first came out people would spend hours of their holiday filming videos so when they got back home they could see what they had missed and subject others to hours and hours of amateur VHS quality poorly shot shaky directionless videos.

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Just Chat! / Re: How Many Philosophers Agree With J. J. C. Smart?

« on: 28/11/2024 09:49:04 »

Was it written for laymen, or is it taught in places like universities?

I think you will find we are all laymen when judged from a position of interlectual liberalism and all universities are in a metaphysical position are non productive consideration centres of the Fourth dimension.